Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hanh vai » hanh vi, hanh va, hanh tai
tu sach » thu sach, su sach, te sach
vai cua » dai cua, hai cua, lai cua
hieu ve » hieu va, hieu van
ky tang » ky nang, ky dang, kho tang
tang ma » mang may, tang van
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
ve cam » ve cham, ve cac, va cam
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (thuoc sach)) ky tang ma hoi. hieu ve cam ((xuc va) or (tuc va)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) ky tang ma hoi. hieu ve cam ((xuc va) OR (tuc va)) hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuoc sach)) ky tang ma hoi. hieu ve cam ((xuc va) or (tuc va)) hanh vai cua tre*.